What are particles in the Wolfram model?

The model proposes that a particle is not a separate kind of stuff but a persistent local feature of the hypergraph — a knot or pocket of structure that keeps reconstituting itself as the rule fires and moves around, instead of dissolving back into the background. Since everything is made of the same hypergraph, there is nothing else for a particle to be made of. [conjecture] This is a picture, not a result: no specific particle (not even the electron) has been identified, and there is no rule yet for which knots are stable or what their masses would be.